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Soloha48 [4]
3 years ago
8

What is the sign of enthalpy change for (a), an endothermic reaction? (b). an exothermic reaction?

Chemistry
1 answer:
fenix001 [56]3 years ago
8 0

Answer:

The answer is: (a) positive; (b) negative.

Explanation:

The change in enthalpy (ΔH) of a reaction is the amount of energy absorbed or released during a chemical reaction carried out at constant pressure.

a) In an endothermic chemical reaction, heat energy is absorbed by the system from the surrounding. Therefore, the sign of enthalpy change for an endothermic process is positive, ΔH= positive.

b) In an exothermic chemical reaction, heat energy is released by the system into the surrounding. Therefore, the sign of enthalpy change for an exothermic process is negative, ΔH= negative.

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riadik2000 [5.3K]

The other students in the lab should be notified next in this type of scenario.

<h3>What is an acid?</h3>

This is a substance which donates protons and is very corrosive. It also turns blue litmus paper red.

When it was spilled and baking soda was used to neutralize it on the floor , it is best to inform the other students too so as to prevent them from being exposed by mistake thereby reducing risk of injury.

Read more about Acid here brainly.com/question/25148363

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5 0
2 years ago
Why do atoms tend to be bonded to other atoms?
Aleks04 [339]

Answer:

Atoms are often more stable when bonded to other atoms

Explanation:

Like for example let's say ionic bonds..... Since one atom has to lose specific electrons to be stable and the other needs the electrons from the other atom to be stable.....

3 0
3 years ago
Read 2 more answers
What volume of 0.194 MNa3PO4 solution is necessary to completely react with 85.5 mL of 0.109 MCuCl2 ?
ira [324]

Answer:

35.9 ml

Explanation:

Start with the balanced equation:

3CuCl2(aq)+2Na3PO4(aq)→Cu3(PO4)2(s)+6NaCl(aq)

This tells us that 3 moles of CuCI2 react with 2 moles Na3PO4-

∴  1 mole CuCl2 will react with 2/3 moles Na3PO4

We know that concentration = moles/volume i.e:

c= n/v

∴n=c×v

∴nCuCl2=0.107×91.01000=9.737×10−3

I divided by 1000 to convert ml to L

∴nNa3PO4=9.737×10−3×23=6.491×10−3

v=nc=6.491×10−30.181=35.86×10−3L

∴v=35.86ml

4 0
2 years ago
A chemist mixes sodium with water and witnesses a violent reaction between the metal and water. this is best classified as
Tema [17]

A law is statement about an observed concept. A theory involves the explanation of scientific concepts or principles. A hypothesis is the predicted explanation about some concepts that has to be tested in order to prove it to be right. An observation is the observing the results of a scientific experiment carried out to test an hypothesis.

Here the given statement 'A chemist mixes sodium with water and witnesses a violent reaction between the metal and water,' can be classified as an observation as it explains what the chemists observes as a result of his chemical experiment or test..

8 0
3 years ago
Write the equation for the reaction described: A solid metal oxide, Ag2O, and hydrogen are the products of the reaction between
Harlamova29_29 [7]

Answer:

2Ag + H2O -----> Ag2O + 2H

Explanation:

2Ag + H2O -----> Ag2O + 2H is the equation of the reaction between metal and steam. Silver reacts with water (steam) forming silver oxide and hydrogen gas. When the metals react with steam it produces the solid metal oxide and hydrogen gas. On the surface o metals, a protective layer of aluminium oxide is formed that keeps water away from the metal so we can say that silver oxide and hydrogen are formed from the reaction of silver metal and steam.

8 0
3 years ago
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